This invention relates to systems and methods for reducing power consumed by an electronics device that includes a display. More particularly, the present invention relates to spatial-based techniques for conserving power based on inactive portions of a display area.
Video output for a desktop or laptop computer typically consumes between 70 and 95 percent of the computer's power budget. Other electronics devices such as handheld portable computing devices and MP3 players include similarly large video consumption rates.
Currently, power conservation techniques alter an entire image at once, such as shutting down a computer after some predetermined time or applying some other ‘sleep’ or ‘hibernate’ mode that turns off all video output for an entire display area.
Many consumers equate antiquated screen savers directed to preventing screen burn-in with a power conservation tool. Screen burn-in, a phenomenon associated with cathode ray tube (CRT) devices, occurs when phosphors on an internal surface of a CRT screen deteriorate over time due to the frequent presence of currents required for creating visual output. Parts of a CRT screen that continually receive fewer video images will not experience as much burn-in as parts that receive more frequent output. Eventually, a noticeable difference grows in a CRT screen between regions of high activity and regions of low activity. Screen savers were thus historically developed for CRT display devices to prevent screen burn-in from accumulating.
In computer operation, a graphics control initiates the screen saver after some predetermined time and replaces computer video content across the entire screen with new and different screen saver video content. Screen savers only reduce power consumption when the energy required for the screen saver video is less than the energy required for the computer content previously displayed. Many screen savers, such as picture slide shows, may consume more energy than the previous video content. In addition, graphics-based user interfaces run a screen saver across an entire screen. These rules intend to protect CRT life, regardless of power consumption.
Based on the foregoing, it should be apparent that improved power conservation techniques would be desirable.